How high can one suck water up a straw ?
Is this analysis and calculation correct ?
================
Straw sucking height limit calculation
Sucking up thru a straw from a height ...limit h = ? m
If the pressure P [=F/A] , the work done to lift the water column to h is
W = F dot s = PA x h/2 [average height = h/2]
The potential energy of the column is PE = ρAhg (h/2) [c of m is in the middle].
When the column rises up to its highest, there is no motion,
so all the energy is potential.
Equating work done to potential energy due to energy conservation
PAh/2 = ρAhg (h/2)
P = ρhg
h = P / ρ g
h = 1.0e5 N/m^2 / (1000 kg/m^3) ( 10 m/s^2)
h = 10 meters
Does that look correct ?
Thanks for your comments
